Chapter 3 Instability

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CHAPTER 3 | Instability

FIGURE 3-10  Coracoid Drill Guide. A: The Coracoid Drill Guide (Arthrex, Inc., Naples, FL) has slots for drilling the coracoid in preparation for Latarjet. B: The elongated slots are placed on the medial surface of the coracoid graft (the side that will rest against the glenoid). The guide facilitates placement of two 4-mm parallel drill holes. C, coracoid graft.

created with the Coracoid Drill Guide) to allow for easy control and positioning of the coracoid graft onto the gle- noid (Fig. 3-10). Three offset sizes are available (4, 6, and 8 mm) to adapt to various graft diameters. Some additional shaping of the graft with a rongeur or a power burr may be required to obtain the best possible fit of the guide against the graft. An optimal fit occurs when the coracoid is slightly below the overhanging offset fin once the pegs are fully engaged (Fig. 3-11). Positioning the Coracoid Graft on the Glenoid and Securing the Graft The glenoid is optimally exposed by placing a Fukuda retractor to lever the humeral head posteriorly and by plac- ing a two-pronged Hohmann retractor medially to retract the medial soft tissues. Proper position of the coracoid bone graft relative to the glenoid is critical. The graft must be placed so that it serves as an extension of the articular arc of the

Grasp the coracoid graft with the grasping Coracoid Drill Guide (Arthrex, Inc., Naples, FL) (Fig. 3-10). Position the guide on the graft so that the elongated clearance slots are on the freshened surface of the coracoid that will even- tually be in contact with the glenoid. The Coracoid Drill Guide allows the surgeon to drill two parallel 4-mm holes through the graft. Care is taken to ensure that the holes are centered on the graft and are perpendicular to the prepared bone surface. Positioning the Parallel Drill Guide on the Graft Prior to the development of the Glenoid Bone Loss Set (Arthrex, Inc., Naples, FL), the coracoid graft had to manu- ally be positioned on the glenoid in a freehand manner. This was technically very difficult and was not easily repro- ducible. The Parallel Drill Guide (Arthrex, Inc., Naples, FL) has greatly simplified this part of the procedure and has also made it very reproducible. The pegs on the Parallel Drill Guide mate with the pre- drilled holes on the coracoid graft (i.e., those that were

FIGURE 3-11  The Parallel Drill Guide (Arthrex, Inc., Naples, FL). A: Pegs on the guide mate with the predrilled holes in the coracoid graft. Different offsets are available to accommodate grafts of varying thickness. A 6-mm offset guide is pictured. B: An optimal fit occurs when the overhanging fin is flush with or slightly above the coracoid graft. C, coracoid graft.